Description: The Laboratory Core will be established to act as the center for the collection, processing, distribution, storage, and testing of specimens obtained from the clinic sites in support of studies being conducted in the projects. The primary objectives of the Laboratory Core are to: (i) act as the central specimen processing and repository for the study of specific specimens as well as specimen extracts, (ii) perform virologic and immunologic assays as indicated in the subprojects, and (iii) to be an intermediary for bring new laboratory technology to the program.